The present disclosure relates generally to wireless networks, and more particularly, to location tracking in wireless networks.
Location tracking is used to determine the location of a device in a wireless network. Location tracking techniques include, for example, distance based techniques such as Time of Arrival (ToA), Time Difference of Arrival (TDoA), and Received Signal Strength Indication (RSSI), and angle based techniques such as Angle of Arrival (AoA). ToA systems are based on measurement of the arrival time of a signal transmitted from a tracked device to several receiving sensors. TDoA techniques use relative time measurements at multiple receiving sensors to identify the location of the tracked device. In RSSI systems, knowledge of the transmitter output power, cable losses, and antenna gains, and received signal strength of a received packet along with an appropriate path loss model allow for calculation of the distance between the tracked device and a tracking device in the wireless network.
Tracking devices collect location information about the tracked device based on transmissions sent from the tracked device. The collected information may be transmitted to a central location, such as a location server.
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